Work rotating apparatus for beam machining having tilt limiting stops

Abstract

A safety structure, for use in a work rotating apparatus for a laser beam machine having a manually rotatable shaft and work holder supported by a frame, comprises a pin and a pair of stops. The stops are separately located along a circular arc which is coaxial with the shaft. The stops contact the pin to limit the angle of rotation of the shaft which prevents the rotatable work holder, and the workpiece held by said work holder, from colliding with the frame.

We claim: 
     
       1. In a work rotating apparatus for a laser beam machine having first and second parts, the first part being a frame and the second part being a shaft supported by said frame for rotation about a first axis, the frame having a portion disposed laterally with respect to said shaft, said work rotating apparatus also having work holding means provided on said shaft, means for rotating said work holding means about a second axis transverse to said first axis, means for manually rotating said shaft whereby said second axis can be tilted, and means for locking said shaft against rotation whereby the second axis can be fixed at any selected one of a plurality of inclinations, wherein the work holding means is positioned in relation to said frame so that, upon excessive rotation of said shaft in either direction, the work holding means, or work held thereby, can collide with said portion of the frame, the improvement comprising a pin, and a pair of stops, said pin being fixed to one of said first and second parts, and the stops being fixed to the other of said first and second parts, the stops being disposed at separate locations on an arc coaxial with said first axis, and the pin being disposed at a distance from said first axis such that it is engageable with one of said stops as the shaft rotates in first direction, and with the other of said stops as the shaft rotates in the opposite direction, the stops being positioned on said arc at locations such that the stops holding means or work held by said work holding means are prevented from colliding with said portion of the frame. 
     
     
       2. A work rotating apparatus according to claim 1 in which the work holding means is positioned in relation to the frame so that, upon excessive rotation of said shaft in either direction, the work holding means, in the absence of work held thereby, would collide with said portion of the frame, and in which the stops are positioned on said arc at locations such that the work holding means are prevented from colliding with said portion of the frame.